UVA 11388 - GCD LCM

#include
int main()
{
int n,m,t;
scanf("%d",&t);
while(t--)
{
    scanf("%d%d",&m,&n);
    if(n%m==0)
    printf("%d %d\n",m,n);
    else
    printf("-1\n");
}
return 0;
}